The tightening or loosening of threaded fasteners such as nuts and bolts is often accomplished by use of a selected socket element which accommodates the size of the particular bolt or nut, with the socket element in turn being releasably attached to a manual or power-driven socket wrench. Such arrangements are well known, and commonly utilized for all types of mechanical devices and structures.
In many instances, however, access to the fastener is complicated by either the remote location of the fastener, or the lack of convenient access due to location of the fastener in a crowded environment. Various extension devices and the like have been developed for use in some of these situations, although accessing a threaded fastener with a conventional socket element and wrench is in many situations extremely difficult and often times impossible to achieve. In particular, in situations where the fastener is disposed in close proximity to some other rigid wall or structure which is disposed closely adjacent and spaced only a small distance from the end of the fastener, accessing the fastener with a socket element is difficult, particularly in those situations wherein the socket element is mounted on and projects sidewardly from a conventional socket wrench, since this overall combination requires significant clearance, and such clearance is often times not available. This becomes particularly difficult in situations where the fastener is positioned not only in a limited clearance environment, but is also remotely located relative to the point of access such that a conventional socket wrench, or the use of conventional extenders, is not possible.
Further, in these situations the very limited access often makes if difficult to apply sufficient torque to facilitate either loosening or tightening of the fastener, and hence this further increases the difficulty of positioning fasteners in such locations.
Accordingly, it is an object of this invention to provide an improved extender-type attachment tool particularly suitable for use with a socket element, which attachment tool facilitates access to a threaded fastener in a situation where the fastener is remotely located and is difficult to access, and which overcomes many of the disadvantages associated with prior structures which have been attempted to be used in such situations.
More specifically, the improved attachment tool functions as an elongate extender and has a socket-receiving opening at one end thereof as defined within a socket driving element, which opening is a through opening to facilitate receiving a socket or like element from either side thereof, the socket element itself preferably having a through opening. The attachment tool is of a narrow or thin dimension transverse to the elongated length thereof to facilitate its insertion into a narrow clearance space, with the drive hub of the removable socket element being accommodated substantially within the thickness of the attachment tool. The other or remote end of the attachment tool has a rotatable drive part which drivingly and internally connects to a socket driving element. The drive part at the remote end of the attachment tool accommodates the drive stud of a driving wrench, such as a conventional manually-activated ratchet wrench or power tool, which wrench or power tool can extend at an angle to the tool to facilitate activation of the driving element.
In a manually-activated embodiment of the attachment tool, the internal drive arrangement provides a torque step up between the drive part and the socket driving element to provide increased torque to facilitate tightening or loosening of a threaded fastener.
A further object of the invention is to provide an improved attachment tool which, in addition to possessing structural and functional advantages as summarized above, in addition incorporates a speed increase mechanism coupled between the drive shaft and the driving ratchet mechanism for increasing the stroke or angle of oscillation of the ratchet mechanism to in turn cause an increase in the angular displacement of the output gear for each revolution of the drive shaft, thereby increasing the output and more specifically the speed or number of revolutions of the output in proportion to the rotational input speed. This thus increases the speed and efficiency of use of the attachment tool.
In the attachment tool of this invention, as aforesaid, the speed increasing mechanism includes an intermediate yoke which is pivotally interconnected between the drive shaft and the oscillating ratchet mechanism, which yoke has an intermediate pivot disposed so as to provide output and input lever arms which define a stroke or displacement increase between the input and output ends thereof, which stroke increase is then applied to the ratchet mechanism and ultimately to the output gear to increase the effective output speed thereof.
Other objects and purposes of the invention will be apparent to persons familiar with structures of this general type upon reading the following specification and inspecting the accompanying drawings.